1. Field of the Invention
The present invention generally relates to a pressure indicating apparatus and particularly to a tire pressure gauge.
2. Description of the Prior Art
Maintaining vehicle tire pressure to that specified by the tire manufacturer is significant in preventing accidents and premature wear. Service and gas stations traditionally have had an air pump with a tire pressure gauge built within available to motorists. However, it has become far too common that those devices are either not available or malfunctioning or are coin-operated. While it is true that many motorists own and utilize their own tire pressure gauge, it is often misplaced.
The prior art discloses tire pressure indicating apparatus of various designs and means: U.S. Pat. No. 4,103,549 to Schmidt discloses a tire valve cap with pressure indicator comprising a housing with spring-loaded diaphragm piston exposed to the tire pressure; U.S. Pat. No. 4,174,673 to Tung et al. discloses a low pressure warning tire air valve cap comprising a cylindrical body, a piston disposed therein, a deformable and a perforated diaphragm; and U.S. Pat. No. 5,115,832 to Higdon et al. discloses a tire pressure gauge and cap apparatus comprising a body tube to be secured to the valve of a conventional tire. Although these prior art patents disclose various tire pressure indicating methods and devices, none of them disclose a tire pressure gauge of the particular type as disclosed and claimed hereinafter.
It is thus a primary objective of the present invention to provide a tire valve cap pressure gauge which has a self-contained pressure indicator.
Another objective of the present invention is to provide a tire valve cap pressure gauge which utilizes a transparent housing having a scale for ready-viewing of pressure level.
Yet another objective of the present invention is to provide a tire valve cap pressure gauge which utilizes an inflatable diaphragm.
Still another objective of the present invention is to provide a tire valve cap pressure gauge which prevents air leakage in the event of valve cap damage.